Restraint system for tubular self-erecting devices

ABSTRACT

A restraint system for a tubular self-erecting device has a self-coiling spiral spring extending inside the tubular device and secured to the outer end thereof. The spring is mounted for winding and unwinding below the tubular device and has means to limit the extension of the spring.

United States Patent. [191.

Snyder et a1.

111- 3,822,874 [451' July 9,1974

[5 RESTRAINT SYSTEM FOR TUBULAR SELF-ERECTING DEVICES [75] Inventors: Kenneth J. Snyder, Perkasie;

Howard C. Valle, Doylestown, both of Pa.

[73] Assignee: Ametek, Inc., New York, NY.

[22] Filed: Jan. 5, 1973 [21] Appl. No.: 321,155

[52] US. Cl 267/156, 187/1, 242/54 R [51] Int. Cl F16f 1/10 [58] Field of Search 242/54 R; 267/156, 155,

[56] References Cited UNITED STATES PATENTS 3,495,687 2/1970 Shirley, .lr et a1 267/156 3,666,220 5/1972 Rider 267/156 Primary Examiner.lames B. Marbert Attorney, Agent, or Firm-Smith, Harding, Earley &. Follmer [5.7] 1 ABSTRACT A restraint system for a tubular self-erecting device has a self-coiling spiral spring extending inside the tubular device and secured to the outer end thereof. The I spring is mounted for winding and unwinding below the tubular device and has means to limit the exten sion of the spring.

6 Claims, 5 Drawing Figures PATENTELEJUL 9:974

FIG. 5.

FIG. 4.

FIG..3.

nates this problem.

1 RESTRAINT SYSTEM FOR TUBULAR SELF-ERECTING DEVICES BACKGROUND OF THE INVENTION It is well known to employ a restraint system for a tubular self-erecting device to limit the erectionof said device. There is need for such a restraint device in many applications of self-erecting tubes such as the tube disclosed in US. Pat. No. 3,467,329. It is known to employ a cord with such tubes to limit their erection. While cords are satisfactory when only a single erection is contemplated, they are unsatisfactory when repeated erection and collapsing of the tube is involved since the cord tends to tangle and get caught up in the coils of the tube. The restraint device of this invention elimi- SUMMARY OF THE INVENTION A restraint system for a tubular self-erecting device has a self-coiling spiral spring extending inside the tubular device and secured to the outer end of the tube. Means support the spring for winding and unwinding and means limit the extension of the spring to correspondingly limit the erection of the self-erecting device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevation of a tubular self-erecting device employing a restraint system of the invention;

FIG. 2 is a front elevation of the tubular device of FIG. 1 partially broken away;

FIG. 3 is a vertical section through the tubular device of FIG. I showing the tubular device in the collapsed condition;

FIG. 4 is a vertical section taken on the plane indicated by the line 44 in FIG. 3, partially broken away, and

' FIG. 5 is an enlarged view, partially broken away, of parts of the device of FIG. 1.

DETAILED DESCRIPTION or AN EMBODIMENT OF THE INVENTION A self-erecting device 2 has a tube 4 comprising helical, axially extending ribbon 6 of spring material which has adjacent turns set to coil tightly in overlapping and telescoping engagement. Tube 4 is of the type disclosed in US. Pat. No. 3,467,329 and has its lower end 8 pivotally connected to the interior of a container 10 by means of a rivet indicated at 12. A tip 16 has a cylindrical portion 18 secured within the upper end of tube 4 and is secured thereto by a rivet 19. As shown in FIG. 3, the tubular device 2 is restrained in the collapsed (stored) position by means of a headed pin 20 which passes freely through brackets 22 and 24 secured to container 10. As thus described, the tubular device 2 is well known to the art. I

An embodiment of the restraint device of the invention will now be described. Container 10 has a base 28 provided with a cavity 30 which acts to support for winding and unwinding a self-coiling spiral spring 32 which has its inner end set into a tight coil 34 which is spot welded to spring 32 at 35. An opening 36 in base 28 is provided for the passage of spring 32 as it winds 6 and unwinds. The outer end 38 of spring 32 IS spot 5 welded at- 39 to the shank 40 of a swivel ball 42 mounted for rotation within a cage housing 44 which 2 is secured to the hollow lowerend 46 of tip 16 to provide for relative rotation of the extended portion of spring 32 and tip 16 which will rotate with tube 4 as it is extended and retracted. Spring 32 advantageously is a noncumulative force coil spring of the type disclosed in US. Pat. No. 2,609,192 (incorporated herein by reference) which has a self-coiling ribbon of spring mate rial having adjacent turns set to tightly coil upon each other. The inner end coil 34 is selected so as to be larger than opening 36.

In operation, when pin 20 is pulled, the tubular device 2 erects into the condition shown in FIGS. 1 and 2. As the device 2 erects it'acts to unwind spring 32 until the spring is fully unwound and the inner end coil 34 is arrested by engaging thewalls of opening 36. At this juncture since the spring 32 can extend no further the erection of the tubular member 2 is halted at the predetermined height desired. It will be evident in designing this system that the self-erecting tubular device 2 .will be designed so that it would erect a greater distance if it were not restrained by spring 32.,

To restore the tubular device to the storage position,

force is exerted in an axial direction on tip 16 until the ribbon 6 has collapsed into the configuration shown in FIG. 3'and the pin is replaced through brackets 22 and 24 to restrain outer movement of tip 16. During this operation as the tube 4 is being collapsed, spring 32 is winding itself up within cavity 30 and continues to do so until fully wound as shown in FIG; 3.

It will be understood that the above described embodiment is illustrative and is not intended to be limit mg.

I We claim:

1. In a device having a self-erecting tube, a restraint system comprising:

a self-coiling spiral spring extending inside the tube,

I means to secure the outer end of said spring to the outer end of the tube,

means to support said spring for winding and unwinding, and

means to limit the extension of said spring on unwinding to limit the erection of the self-erecting tube.

2. A restraint system in accordance with claim 1 in which the spring is a non-cumulative force spring with adjacent turns set to tightly coil on each other.

3. A restraint system in accordance with claim I in which the tube is a helical ribbon of spring material having adjacent turns set to tightly coil in overlapping and telescoping engagement and having swivel means connecting the outer end of the spring to the outer end of the tube.

4. A restraint system in accordance with claim 1 in which the support means comprises means forming a cavity with an opening for the passage of the extending portion of the spring.

5. A restraint system in accordance with claim 4 in which a stop member is secured to the inner end of the spring which is too large to pass through the opening.

spring with adjacent turns set swivel means connecting the outer end of the nonto the tube, and

cumulative force spring to the outer end of the stop means too large to pass through said passage tube, means adjacent the inner end of the nonpassage means in the base to provide for the passage cumulative force spring.

of the non-cumulative force spring from the cavity 5 

1. In a device having a self-erecting tube, a restraint system comprising: a self-coiling spiral spring extending inside the tube, means to secure the outer end of said spring to the outer end of the tube, means to support said spring for winding and unwinding, and means to limit the extension of said spring on unwinding to limit the erection of the self-erecting tube.
 2. A restraint system in accordance with claim 1 in which the spring is a non-cumulative force spring with adjacent turns set to tightly coil on each other.
 3. A restraint system in accordance with claim 1 in which the tube is a helical ribbon of spring material having adjacent turns set to tightly coil in overlapping and telescoping engagement and having swivel means connecting the outer end of the spring to the outer end of the tube.
 4. A restraint system in accordance with claim 1 in which the support means comprises means forming a cavity with an opening for the passage of the extending portion of the spring.
 5. A restraint system in accordance with claim 4 in which a stop member is secured to the inner end of the spring which is too large to pass through the opening.
 6. In a device having a self-erecting tube with a helical ribbon of spring material, a restraint system comprising: a non-cumulative force spring with adjacent turns set to tightly coil on each other mounted in a cavity in said base, swivel means connecting the outer end of the non-cumulative force spring to the outer end of the tube, passage means in the base to provide for the passage of the non-cumulative force spring from the cavity to the tube, and stop means too large to pass through said passage means adjacent the inner end of the non-cumulative force spring. 